Anesthesia in ornamental fish for clinical examination and treatment
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Abstract
The initial step of health status evaluation in ornamental fish in the veterinary clinic or hospital is physical restraint during the clinical examination. However, unexpected problems such as stress and injury among examined fish and practitioners might happen. Therefore, chemical restraint by anesthesia is aimed at veterinary work, for example; physical examination, tissue and blood sampling, and drug administration. The unconsciousness of fish during anesthesia occurs due to depression of the central nervous system or blockage of the sensory nerve pulse depending on the concentration of anesthetic agents, which can be categorized into 4 levels of anesthesia including level 1: sedation, level 2: narcosis, level 3: anesthesia, and level 4: medullary collapse. In addition, there are 3 planes at the stage of anesthesia namely plane 1: light anesthesia, plane 2: moderate anesthesia, and plane 3: deep anesthesia. Practically, the recommended level or stage of anesthesia for fish examination that causes total insensibility is stage 3 plane 2 suitable for fish examination and soft surgery. To date, the common anesthetics used for aquatic animal restraints include MS-222, eugenol, benzocaine, phenoxyethanol, and quinaldine, which must be prepared as a stock solution with proper pH adjustment before dissolving into the water of an anesthetic tank. In addition, there are some important considerations for practical anesthesia in fish during process including preparation of both fish and practitioner before anesthesia, anesthesia, and health assessment, and the recovery of fish post insentient.
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Journal of TCI is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)
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